There are nodes that can be found on the cliffs lining the rivers of Alderan. From the node you will receive a Rouch Magenta Crystal Shard that must be taken to Korriban to refine into Pristine Adegan Crystals. The alderan nodes are on no less than a 2 hour spanwn timer and I have only seen oneone spawn in this two hour time period. Archaeology is not needed to farm these and there will be no indication of it's location on your minimap.